Connector for a millimeter waveguide

ABSTRACT

A connector for millimeter or other types waveguides, wherein packing material and push rings are firmly disposed between connecting sleeve and waveguides with spacer rings provided between the connecting sleeve and waveguides. Alignment of the waveguides is effected at the time of connection. The interconnecting surfaces of the parts are superfine finished so that tolerances are met and bending amount at the connecting parts is kept minimal.

nited States Patent 1191 Hara et al.

[ 1 CONNECTOR FOR A MILLIMETER.

WAVEGUIDE [75] Inventors: Atsushi Ham, Tokyo; Hisao Naganuma; Akio Takai, both of Yokohama, all of Japan [73] Assignee: Nippon Kokan Kabushiki Kaisha,

Tokyo,Japan [22] Filed: May 24, 1971 [2]] Appl. No.: 146,321

C [30] Foreign Application Priority Data 52 u;s.c1...l ..285/39,28S/369,285/414, 333/98R 51 Int.Cl ..F16119/02 [58] Field of Search ..285/369, 353, 4'14, 115, 116, 285/39; 333/98 R; 151/15 [56] References Cited 'UNlTED STATES PATENTS 3,500,264 3/1970 Floyd .L ..333/98 R [451 Jan. 23, 1973 3,560, 29 2/1971 1=16 1 ..333/98 R 174,572 3/1876 Rankin ....285/414 x 318,356 5/1885 Cogan ....285/369 x 607,180 7/1898 LalldiS ....285/414 x 1,506,564 8/1924 Cattoni.... ..285/39 x 4/1945 Barr ..151/15 Primary Examiner-Thomas F. Callaghan Attorriey-Moonray Kojima [57] ABSTRACT v A connector for millimeter or other types waveguides, wherein packing material and push rings are firmly disposed between connecting sleeve and waveguides with spacer rings provided between the connecting sleeve and waveguides. Alignment of the waveguides is effected at the time of connection. The interconnecting surfaces of the parts are superfine finished so that tolerances are met and bending amount at the connecting parts is kept minimal.

4 Claims, 2 Drawing Figures PATENTEUJANZB I975 Arms: HAM

fllmo AMMNHHA hKIo mm INVENTOR.

,ormwey 1 CONNECTOR FOR A MlLLlMETER WAVEGUIDE BACKGROUND OF INVENTION This invention relates to a connector for a millimeter or other types of waveguides. Such waveguides can be disposed in the ground or in the air and can be used to transmit different wave signals.

A variety of conventional millimeter waveguides and connectors therefor exist. Usually the inner diameter of these is about to 60 mm. There are two kinds or types of waveguides. One type has a copper plating with a resin lining on its inner surface. Another type is the helical waveguide in which a wire is wound around its inner surface. Gas having a pressure of about 1 Kg/cm is sealed in the waveguides.

The signals being transmitted by prior guides were often impaired, by such factors as unevenness or bending of the inner surface of the waveguide and warping or folding of a core thereof. To prevent this impairment of transmission characteristic of the waves, tolerances are usually strictly set,'for example, by staggering the core at the connecting part, and bending it either at the time of connecting the connecting part in the straight condition, or at the time of bending the passage to about 30 m radius of curvature. There are various ways to accomplish the foregoing. However, it is still difficult to obtain precise alignment with less than 0.05 mm being the permissible error. It is also difficult to keep the tolerance of bending to a bending amount which is less than 0.3 m radius, in the case of the straight line connecting, and less than 1 m radius in the case of the bending line connecting. Also, the prior art structures are complex, difficult to manufacture, inefficient and difficult to connect, andexpensive. v

One prior art structure is a bat flange. This structure isrelatively air tight, and prevents warping of the core. However its outer diameter is so large that a plurality of pipes cannot beprovided at one pit or stand. Thus, this type of flange is not suitable for practical use.

Another prior art type -is the twist waveguide. This type has a long flat processing part. But, disadvantageously, if a small amount of dust is deposited on v the body, nibbles are caused on the body-and sleeve and prevents airtight seal, and lowers working efficien- A third prior art type is a caulking or spring waveguide. Although this type has some merit, it has shortcomings in being difficult to connect.

To reduce ,these shortcomings, a fourth type of'wave guide has been proposed using an O-ring. In this type of waveguide, a waveguide is screwed into a connecting sleeve and thereafter the O-ring is temporarily placed outside of the connector with a driver like tool. Although this typeof connector has some merit, the mounting step maycause flaws to the O-ring, or cause it to be inexactly set. In either case, there is lack of air tight seal.

SUMMARY OF INVENTION In order to prevent such, staggering of the core,'the inventors have proposed that super fine tinishings be effected on each connecting surface, such as of the connecting parts of the waveguide and of the connecting sleeve and close tolerances be given to the mountings of the members. In order to keep the bending amount within a certain tolerance, the clearance is made small between the outer surface of the waveguide and the innersurface of a push ring which is pressed through rubber packing material. The tolerances mentioned above are generally those which are acceptable. Nitrogen gas which is introduced into the waveguide is sealed with a wedge shaped rubber packing in order to improve the transmission characteristic of the wave.

Copending US. Pat. application, Ser. No. 91791 shows some of these items.

A system of double tubes (sheath tubes) is often adopted for fabricating millimeter waveguides. The connection is performed while the waveguide is being brought into the connect-sleeve. It is preferable that this moving force be obtained by screws formed at the central part of the connecting sleeve as well as a screw structure or threads located at end parts of the interconnecting waveguides. Such connectors may display excellent performance at the time of arrangement of the straight passage. However, it is difficult to screw the wave guides into the connecting sleeve for parts of different shaped waveguides or those between different construction. Thus, the connecting purpose might not be exactly accomplished.

Also, when it is desired to exchange the halfways only of passages, it is impossible to cut off those parts in the vicinity of the connectors by using gas or other types of cutting machines. Moreover, the connectors are connected by moving the waveguide to make the axial direction thereof by use of the length of the threaded part, which is disadvantageous and troublesome.

An object of this invention is to remove the foregoing and other disadvantages of the prior art arrangements. Other objects of the invention are to keep substantially perfect air tight seal of the gas in the wave guide, to improve the strength of the mechanical connector, to obtain a highly precise alignment which is kept within certain tolerances, such as those discussed above, to simplify connecting and exchange at the halfways of the passages, and to heighten the workings thereof.

For such purposes, the invention employs two spacer rings to engage by means of threads the waveguides with connecting sleeves having therein the spacer rings.

Connecting surfaces are respectively formed between I v and the inner surfaces of the connecting sleevesand the spacer rings. The waveguides are set while the alignment is being effected automatically at the two connecting surfaces. The spacer rings are aligned in the inside of the'connecting sleeves. The air tight condition is provided by pressing the packings while the exact alignment is being effected. Both waveguides are easily connected by mounting the push rings onto the outer parts of the waveguides, subsequently positioning the connecting sleeve having at its inner sidethe spacer rings between the end portions of both waveguides, and rotating the push rings. The waveguides are easily and exactly exchanged since they are fabricated by removing either of the push rings, instead of moving and/or rotating the waveguide as done in the prior art.

A further object of the invention is to obtain a waveguide which may be used to connect differently shaped waveguides or connecting parts between structures.

Another object is to obtain a strong connector for waveguides of comparatively small size in comparison with the conventional flanged one or others while maintaining the other favorable characteristics. Since the invention disposes the spacer rings, the connecting sleeve and push rings on the outer surface of the waveguides, these members are not bulky. Also, any protective coating would be on the outside and be of small size or diameter; thus, operation and utility would be improved.

DESCRIPTION OF DRAWING FIG. 1 is a side view, partially in section, showing an illustrative embodiment of the invention; and

FIG. 2 depicts a cross-sectional view of another spacer ring.

DETAILED DESCRIPTION OF DRAWING In FIG. 1 waveguides (1) and (2), which are to be connected, namely at the outer peripheries of the end portions thereof, are depicted having threads (11) and (12) formed at the ends. Spacer rings (3) and (4) are screwed thereon to face each other. The rings (3) and (4) are formed with a first connecting surface A of superfine finishing, the connecting surface being between the inner surface thereof and the outer surface of the waveguides. A second chamfered connecting surface B of superfine finishing of substantially the correct size is located between the outer surface of spacer rings (3) and (4) and the inner surface of connecting sleeve (10).

Attaching portion (19) is formed between waveguide (1) and the inner surface of one end portion of connecting sleeve (10) in order to attach a wedge shaped rubber packing (5) and a push ring (6). Attaching portion (18) is formed between waveguide (2) and the inner surface of another end portion of connecting sleeve in opposition to the attaching portion (19), in order to attach a packing (8) and a'push ring (7). Packings (5) and (8) are provided, respectively, with back-up rings (5') and (8') to enable the push rings to easily rotate.

There are precisely formed third connecting surfaces C of super fine finishing on the inner surfaces of push rings (6) and (7). Threads (23) and (24) are formed on the outer surfaces push rings (6) and (7) to be threaded into connecting sleeve (10). An O-ring (9) of circular cross section is furnished between the end portion of spacer ring (4) and packing (8) as depicted. Threads (14) are formed between connecting sleeve (10) and the outer circumference of the spacer ring (4) located behind O-ring (9). The reference numerals (l6) and (17) are holes formed in the push rings (6) and (7) and used for rotating the push rings. Number denotes a concave shaped opening formed at the center of push ring (7).

To connect the waveguides, push ring (6), packing (5) having the back-up ring (5') and connecting sleeve (10) are firmly mounted onto the outside of the end portion of waveguide (1), while push ring (7), packing (8) having back-up ring (8) and O-ring (9) are mounted in the same manner onto the end portion of waveguide (2). The spacer rings (3) and (4) are screwed onto threads (11) and (12) at the end portions of the waveguides to be connected. Thereafter the con necting sleeve (10) which has in the meantime been mounted on the waveguide (1) is brought to the end portion of guide (2) to screw into with the spacer ring (4). The connecting sleeve (10) has formed at its inside a convex portion (13) which contacts the end portion of spacer ring (3) so that connecting sleeve (10) and spacer ring (4) are fixed at a desired position. As the threads may be right handed, connecting sleeve (10) may be screwed to the right at the time of connecting of connecting sleeve (10) and spacer ring (4). This clamps or tightens thread (12) through thread (14) and thus waveguide (2) and spacer ring (4) are connected thereby to subsequently tighten or clamp thread (14).

In case thread (11) is comparatively low in thread number, and when connecting sleeve (10) is screwed to the right, spacer ring (3) may come out from the waveguide because of the friction between connecting surface B of the superfine finishing and convex portion (13). However, since connecting sleeve (10) is provided at its end portion with convex portion (13), spacer ring (3) contacts with the end portion of spacer ring (4) to prevent it from coming out. In this way, connecting sleeve (10) may be positioned at the desired location. When it is necessary that spacer ring (3) be fastened securely or locked, this spacer ring (3) may be made as a lock nut, such as that shown in FIG. 2.

In FIG. 2, there is depicted a lock nut comprising a first piece (3a) and a second piece (3b) and engaging steps (21) and (22) which may be mutually engaged.

After waveguides (1) and (2), spacer rings (3) and (4) and connecting sleeve (10) are fixed at the desired location, the wedge shaped rubber packing (5) is mounted on the outer surface of waveguide (1) and between the guide (1) and connecting sleeve (10). Push ring (6) is then set. Also, on the outer surface of waveguide (2), O-ring (9) and packing (8) are set with push ring (7). Thus, the connection is completed.

According to the principles of the invention, by precisely finishing surfaces A and B of the respective spacer rings (3) and (4), the waveguides (1) and (2) are substantially prevented from warping at the core. Furthermore, bending is prevented by finishing surface C. Thus, the rigid connecting conditions are satisfied for connectors of waveguides. Gaseous material such as nitrogen gas, having a pressure of from 0.5 to 1.5 Kg/cm is sealed in the waveguides (1) and (2). The sealed or airtight condition is kept with the wedge shaped rubber packings (5) and (8) and the O-ring, to thereby produce a connector for waveguides which does not impair the transmission characteristics of the waves. The connection can also be effected for different types and shapes of waveguides.

The foregoing is intended to be only illustrative of the principles of this invention; numberous other variations and modifications would be evident to those skilled in the art, and such variations and modifications which depend upon the principles of this invention are to be considered within the scope and spirit of this invention.

What is claimed is:

1. Device for connecting the end portions ofa pair of wave guides, said end portions having threads on the outer surfaces thereof, said device comprising A. spacer means comprising a pair of cylindrical sleeves having threads on the inner surface thereof suitable for engagement with said threads of said wave guides when in a connected position and having cylindrical surfaces for engaging cylindrical surfaces of said wave guides adjacent their threads;

B. connecting means comprising sleeve means for fitting about and interconnecting said pair of cylindrical sleeves and said end portions of said wave guide in said connected position,

said connecting means having toward one end thereof a convex portion for holding in said connected position the non-engaged end of one of said pair of cylindrical sleeves and having toward the other endthereof thread means for engaging the non-engaged end of the other of said pair of cylindrical sleeves, said sleeve means having an internal cylindrical surface engaging cylindrical surfaces on said spacers; V

C. packing means comprising a pair of wedge shaped packing material disposed between the ends of said sleeve means and the outer surface of said wave guide; and

D. means for pressing and holding said pair of wedge shaped packing material between said sleeve means and said outer surface of said wave guide thereby to seal said wave guide, said pressing and holding means having internal cylinderical surfaces engaging cylindrical surfaces on said wave guides, all said cylindrical surfaces having a superfine finish.

2. Device of claim 1, wherein an O-ring means is positioned between another end portion of said spacer means and said wedge shaped material.

3. Device of claim 1, wherein said spacer means comprises a lock nut type system having a first piece and a second piece both shaped to be mutually engageable with each other.

4. Device of claim 1, wherein said pressing and holding ring means has at least one hole therein for rotating said pressing and holding means. 

1. Device for connecting the end portions of a pair of wave guides, said end portions having threads on the outer surfaces thereof, said device comprising A. spacer means comprising a pair of cylindrical sleeves having threads on the inner surface thereof suitable for engagement with said threads of said wave guides when in a connected position and having cylindrical surfaces for engaging cylindrical surfaces of said wave guides adjacent their threads; B. connecting means comprising sleeve means for fitting about and interconnecting said pair of cylindrical sleeves and said end portions of said wave guide in said connected position, said connecting means having toward one end thereof a convex portion for holding in said connected position the non-engaged end of one of said pair of cylindrical sleeves and having toward the other end thereof thread means for engaging the non-engaged end of the other of said pair of cylindrical sleeves, said sleeve means having an internal cylindrical surface engaging cylindrical surfaces on said spacers; C. packing means comprising a pair of wedge shaped packing material disposed between the ends of said sleeve means and the outer surface of said wave guide; and D. means for pressing and holding said pair of wedge shaped packing material between said sleeve means and said outer surface of said wave guide thereby to seal said wave guide, said pressing and holding means having internal cylinderical surfaces engaging cylindrical surfaces on said wave guides, all said cylindrical surfaces having a superfine finish.
 2. Device of claim 1, wherein an O-ring means is positioned between another end portion of said spacer means and said wedge shaped materiaL.
 3. Device of claim 1, wherein said spacer means comprises a lock nut type system having a first piece and a second piece both shaped to be mutually engageable with each other.
 4. Device of claim 1, wherein said pressing and holding ring means has at least one hole therein for rotating said pressing and holding means. 